1. Field of the Invention
The described technology relates to a lighting apparatus. In some embodiments, the described technology relates to an organic light emitting diode lighting apparatus that uses an organic light emitting diode.
2. Description of the Related Art
An organic light emitting diode (OLED) has a hole injection electrode, an organic emission layer, and an electron injection electrode. The OLED emits light using energy generated when excitons produced by electron-hole combinations in the organic emission layer drop from an excited state to a ground state.
An organic light emitting diode lighting apparatus is a lighting apparatus using an organic light emitting diode. The organic light emitting diode lighting apparatus can be readily used as a surface light source. Thus, the organic light emitting diode lighting apparatus is used for various purposes while retaining the advantages of the surface light source, and the range of applications thereof is gradually expanding.
In the case of an organic light emitting diode lighting apparatus emitting light of one color, overall current supplied to an organic light emitting diode can be controlled through a single line. In the case of an organic light emitting diode lighting apparatus emitting light of various colors or luminance for which each portion has to be controlled, it is necessary to use multiple lines that can divide the organic light emitting diode into a number of cells and supply different power to each cell.
However, the use of multiple lines may lead to a complex structure due to space limitations, and may cause phenomena such as a voltage drop (IR drop).
Moreover, an organic light emitting diode lighting apparatus emitting white light is mainly used. Further, it is required for the organic light emitting diode lighting apparatus to have the function of variably adjusting the color temperature of white light according to the surrounding environment of a place where the organic light emitting diode lighting apparatus is used.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.